TM 1-1520-265-23
2.27.3.7 Marking and Recording of Inspection Results. Mark and record inspection results as required by paragraph 1.3.
2.27.3.8 Demagnetization. With the switch remaining in the AC position, place the probe/yoke legs in the same position
used for magnetizing. Press the test switch and withdraw the probe/yoke from the part for a distance of two feet before
releasing the switch.
2.27.4 Backup Method. None required.
2.27.5 System Securing. Clean the pitch beam washer thoroughly to remove all residual magnetic particle media. Refer
to Post Cleaning and Restoration of Part or Area After NDI, paragraph 1.4.16. The pitch beam washer requires
installation in accordance with the applicable technical manuals listed in Table 1-1.
2.28 PITCH BEAM RETAINING NUT (MT).
2.28.1 Description (Figure 2-1. Index No. 28). The pitch beam retaining nut retains the pitch beam to the tail rotor
gearbox shaft.
2.28.2 Defects. This inspection is used to verify crack indications found visually on the pitch beam retaining nut. No
cracks are allowed.
2.28.3 Primary Method. Magnetic Particle.
2.28.3.1 NDI Equipment and Materials. (Refer to Appendix B.)
a.
Magnetic Particle Inspection Probe/Yoke
b.
Magnetometer
c.
Black Light
d.
Fluorescent Magnetic Particles, refer to Table 1-8
e.
Consumable Materials, refer to Table 1-8
f.
Aircraft Marking Pencil, refer to Table 1-8
2.28.3.2 Preparation of Helicopter. The helicopter shall be prepared for safe ground maintenance. A partial inspection
for cause (visual indications, sites of mechanical damage, corrosion, etc.) may be performed on all exposed surfaces of
the installed part using applicable positions of this procedure. If required, the pitch beam retaining nut shall be removed
in accordance with the applicable technical manuals listed in Table 1-1.
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